diff options
author | Timothy Arceri <[email protected]> | 2017-01-12 17:01:03 +1100 |
---|---|---|
committer | Timothy Arceri <[email protected]> | 2017-04-24 12:08:14 +1000 |
commit | 83f7fdf83a0546e477aba7fb3685cf78588ea2be (patch) | |
tree | e1297a8971f8c45b61473f13e9454573d788c5e9 | |
parent | 18947fde7ad60859ca1e843aaacf4f5db3c72b91 (diff) |
nir: add flt comparision simplification
Didn't turn out as useful as I'd hoped, but it will help alot more on
i965 by reducing regressions when we drop brw_do_channel_expressions()
and brw_do_vector_splitting().
I'm not sure how much sense 'is_not_used_by_conditional' makes on
platforms other than i965 but since this is a new opt it at least
won't do any harm.
shader-db BDW:
total instructions in shared programs: 13029581 -> 13029415 (-0.00%)
instructions in affected programs: 15268 -> 15102 (-1.09%)
helped: 86
HURT: 0
total cycles in shared programs: 247038346 -> 247036198 (-0.00%)
cycles in affected programs: 692634 -> 690486 (-0.31%)
helped: 183
HURT: 27
Reviewed-by: Elie Tournier <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>
-rw-r--r-- | src/compiler/nir/nir_opt_algebraic.py | 4 | ||||
-rw-r--r-- | src/compiler/nir/nir_search_helpers.h | 15 |
2 files changed, 19 insertions, 0 deletions
diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index 49c1460e25a..bd65eff8b59 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -158,6 +158,10 @@ optimizations = [ # a != 0.0 (('flt', 0.0, ('fabs', a)), ('fne', a, 0.0)), + # ignore this opt when the result is used by a bcsel or if so we can make + # use of conditional modifiers on supported hardware. + (('flt(is_not_used_by_conditional)', ('fadd(is_used_once)', a, ('fneg', b)), 0.0), ('flt', a, b)), + (('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)), (('bcsel', ('flt', b, a), b, a), ('fmin', a, b)), (('bcsel', ('flt', a, b), b, a), ('fmax', a, b)), diff --git a/src/compiler/nir/nir_search_helpers.h b/src/compiler/nir/nir_search_helpers.h index faa3bdfd12b..7decf6582a7 100644 --- a/src/compiler/nir/nir_search_helpers.h +++ b/src/compiler/nir/nir_search_helpers.h @@ -158,4 +158,19 @@ is_not_used_by_if(nir_alu_instr *instr) return list_empty(&instr->dest.dest.ssa.if_uses); } +static inline bool +is_not_used_by_conditional(nir_alu_instr *instr) +{ + if (!is_not_used_by_if(instr)) + return false; + + nir_foreach_use(use, &instr->dest.dest.ssa) { + if (use->parent_instr->type == nir_instr_type_alu && + nir_instr_as_alu(use->parent_instr)->op == nir_op_bcsel) + return false; + } + + return true; +} + #endif /* _NIR_SEARCH_ */ |